H G Zandstra. (1981). A methodology for on-farm cropping systems research. Philippines: IRRI.
Chicago Style aipamenaH G Zandstra. A Methodology for On-farm Cropping Systems Research. Philippines: IRRI, 1981.
MLA aipamenaH G Zandstra. A Methodology for On-farm Cropping Systems Research. Philippines: IRRI, 1981.
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